There is no limit on TB47s in your carry on. I suppose as many as you can fit. I have 5 tb47s and have two TB48s on backorder, its how i plan to travel.
Granger, the charger is in stock at www.allerc.com. Dont forget to grab the power cable for the charger too.
http://www.allerc.com/dji-inspire-1-power-adapter-without-ac-cable-p-9714.html...